Initially central pontin myelinolysis was associated with alcoholism and later with hyponatraemia and particularly the correction rate. The diagnosis is made by characteristic symptoms and cerebral MRI with areas of hyperintensity on T2-weighted images. Outcome varies, mortality is high and most survivors have some degree of neurological deficit. There is no treatment and supportive therapy remains the only option with possible recovery within 6-8 weeks. Hyponatraemia can safely be corrected at a rate of no more than 10 mmol/l within the first 24 hours and 18 mmol/l within 48 hours.